The invention concerns a closing device for a lock which lock possesses a forwardly movable and retractable, pivoting bolt with an arresting latch.
Known door locks exhibit a catch for locking and a bolt for securing the door. The bolt, emerging from the door lock, engages itself in a recess of the door framing or in a opening of a metal plate, so that the door becomes locked. This is carried out with the aid of a closing/opening operating means, i.e. a key and/or a locking cylinder. An arresting latch retains the bolt in its forwardly positioned state. When the bolt is to be retracted by the said operating means, the door can once again be opened upon activation of the arresting latch.
Conventional locks have either a horizontally slidable or a pivoting bolt. Locks with the latter bolt are accordingly designated as xe2x80x9cpivot locksxe2x80x9d. Insertable locks are known, which are placed into a lock-recess in the door panel and are secured by screws. Box locks are fastened in a side recess of the door panel.
Without an appropriate key, these locks can be opened relatively simply by a lock-pick or by boring, whereby, in either case, entry into the locking mechanism is effected. In order to make door opening more difficult without a suitable key, safety-lock cylinders find use. Covers for the locks or a metal plate on the outside of the door offer protection from boring into the lock.
A safety locking apparatus is disclosed by DE 38 19 070 C1, which is applicable to additional locking security of doors. This does not function, however, with a lock in which the bolt moves forwards and backwards.
Again, DE 44 25 313 A1 proposes an arrangement comprised of a lock and a closure apparatus, wherein the closure apparatus possesses a separate security bolt, which is to be found in the door framing. This security bolt enters into a recess in the door panel.
DE 196 01 959 A1 teaches of a lock, which, by means of a transponder, can be activated without being touched. The mechanical locking mechanism of this lock, however, has not been described.
Thus the invention has the purpose of creating a closing device for a pivot lock, which offers increased safety against unauthorized unlocking and opening by lever actuated tools, but for which additional security bolts or the like are not necessary.
This purpose is achieved, in accord with the invention, with the features of claim 1.
The invented lock apparatus encompasses a closure device to receive the pivoting bolt in its forward locking position. The closure device can be sheet metal, which can be screwed into either the door framing or an inset housing in said door framing or yet, the closure device can be integral with the door framing or the said inset housing.
The security of the lock is increased by a locking/unlocking arrangement, which blocks the pivoting bolt in its forward placement against retraction. In the locked condition, invasive mechanical attack of the lock-cylinder or pivot-lock on the door cannot bring about any movement of the bolt. Even when the closure cylinder is turned back, or the lock operated by a skeleton key, or bored into, the bolt cannot be retracted. Since the security locking device is in the door frame or the masonry, it is protected from attack. The pivoting bolt can only be retracted by authorized release.
The lock/unlock device is fully independent of the locking system of the lock. Since two independent closure mechanisms are involved, the lock cannot be unlocked by a non-authorized person even with the proper key. The closure device can thus not only contribute to a higher degree of security, but also can be put to use by persons of upper supervisory levels to prevent entry by persons, who may possess a key which fits the lock. In cases of need, the closure device permits a central removal of the blocking of the bolt.
The lock/unlock arrangement can be integrated into a conventional lock housing, which is set into the door frame or the masonry thereof
For the security of the pivoting bolt against retraction, the lock/unlock arrangement exhibits at least one locking device, which can be inserted into or withdrawn from the forward and retracting zone of the pivoting bolt, i.e. the said device can be thrust forward or pulled back. The locking device forms a detent, which prevents the pivoting bolt from being retracted from its forward locked position.
In a favorable embodiment, the lock/unlock arrangement includes a sender for the emitting of a coded lock/unlock-signal to a receiver for the input of said coded lock/unlock signal to an activation means, with which the locking device is caused to enter or leave, that is, move forward or back, in the forward and retracting zone of the bolt, when the receiver receives the lock/unlock signal. The lock can correspondingly be only opened, if not only the authorized key, but also a sender with the authorized code is present. Even when the code of the sender is stolen, an opening of the lock is possible only through mechanical destruction. In the latter event, at least knowledge of the break-in can be obtained.
The sender and the receiver can emit and receive radio signals. It is also possible that an optical sender can be used. The use of the known transponder with the non-contact reader or other code card scanner is a favorable arrangement.
Advantageously, two blocking elements are provided, which can bar the locking movement of the pivoting bolt from two sides. The locking, however, can be effected from only one side. The blocking elements are preferably, two oppositely situated spheres. Alternately, the blocking elements can be provided as rods or the like.
In another advantageous embodiment, the activation means comprises an obstructing slider, which can be part of the sphere support surfaces, which surfaces then run at such a slant, that the spheres, upon the displacement of said slider, are pushed in one direction, and again, when pushed in the other direction, are released.
Upon an effort, to retract the pivoting bolt by force, then the pivoting bolt impacts against the blocking spheres, which abut the support surfaces of the slider, so that the locking path is blocked. The activation of the blocking slider can be accomplished either electronically or with an electric motor powered positioning device.
The metal plate of the blocking mechanism, in the open position, or the pivoting bolt, can be spring loaded against retraction from the secure position.